DESCRIPTION: This application is focused on the analysis of mechanisms and functions of MT-based motors that the investigators postulate drive specific transport event that occurs during early development. They propose to : 1) characterize the structure, function and domain organization of a putative minus-end-directed kinesin holoenzyme and to analyze its role in nuclear transport and mitosis; 2) to further analyze structure-function relationships in the morphogenesis and function of mitotic spindles; 3) to biochemically characterize the vesicular cargo of the sea urchin embryonic mitotic spindle for delivery to different destinations and 4) to purify the Drosophila Nod chromosomal kinesin-like motor from transgenic fly lines, in order to analyze the mechanism by which it transports chromosomes along MTs.